<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    div:not(#app){
      padding: 50px;
    }
    .div1{
      background-color: rgb(190, 105, 105);
    }
    .div2{
      background-color: rgb(122, 190, 105);
    }
    .div3{
      background-color: rgb(42, 140, 165);
    }
  </style>
</head>

<body>
  <div id="app">
    <div class="div1" @click="fn1">
      <div class="div2" @click="fn2">
        <div class="div3" @click="fn3"></div>
      </div>
    </div>
  </div>
  <script src="./vue.js"></script>
  <script>
  
    const vm = new Vue({
      el: '#app',
      methods: {
        fn3(e){
          e.stopPropagation();
          alert(3)
        },
        fn2(){
          alert(2)
        },
        fn1(){
          alert(1)
        }
      }
    })
    
  </script>
</body>

</html>